Assessing the Risks Associated with MRI in Patients with a Pacemaker or Defibrillator.

BACKGROUND: The presence of a cardiovascular implantable electronic device has long been a contraindication for the performance of magnetic resonance imaging (MRI). We established a prospective registry to determine the risks associated with MRI at a magnetic field strength of 1.5 tesla for patients who had a pacemaker or implantable cardioverter-defibrillator (ICD) that was "non-MRI-conditional" (i.e., not approved by the Food and Drug Administration for MRI scanning). METHODS: Patients in the registry were referred for clinically indicated nonthoracic MRI at a field strength of 1.5 tesla. Devices were interrogated before and after MRI with the use of a standardized protocol and were appropriately reprogrammed before the scanning. The primary end points were death, generator or lead failure, induced arrhythmia, loss of capture, or electrical reset during the scanning. The secondary end points were changes in device settings. RESULTS: MRI was performed in 1000 cases in which patients had a pacemaker and in 500 cases in which patients had an ICD. No deaths, lead failures, losses of capture, or ventricular arrhythmias occurred during MRI. One ICD generator could not be interrogated after MRI and required immediate replacement; the device had not been appropriately programmed per protocol before the MRI. We observed six cases of self-terminating atrial fibrillation or flutter and six cases of partial electrical reset. Changes in lead impedance, pacing threshold, battery voltage, and P-wave and R-wave amplitude exceeded prespecified thresholds in a small number of cases. Repeat MRI was not associated with an increase in adverse events. CONCLUSIONS: In this study, device or lead failure did not occur in any patient with a non-MRI-conditional pacemaker or ICD who underwent clinically indicated nonthoracic MRI at 1.5 tesla, was appropriately screened, and had the device reprogrammed in accordance with the prespecified protocol. (Funded by St. Jude Medical and others; MagnaSafe ClinicalTrials.gov number, NCT00907361 .).

The global cardiovascular magnetic resonance registry (GCMR) of the society for cardiovascular magnetic resonance (SCMR): its goals, rationale, data infrastructure, and current developments.

BACKGROUND: With multifaceted imaging capabilities, cardiovascular magnetic resonance (CMR) is playing a progressively increasing role in the management of various cardiac conditions. A global registry that harmonizes data from international centers, with participation policies that aim to be open and inclusive of all CMR programs, can support future evidence-based growth in CMR. METHODS: The Global CMR Registry (GCMR) was established in 2013 under the auspices of the Society for Cardiovascular Magnetic Resonance (SCMR). The GCMR team has developed a web-based data infrastructure, data use policy and participation agreement, data-harmonizing methods, and site-training tools based on results from an international survey of CMR programs. RESULTS: At present, 17 CMR programs have established a legal agreement to participate in GCMR, amongst them 10 have contributed CMR data, totaling 62,456 studies. There is currently a predominance of CMR centers with more than 10 years of experience (65%), and the majority are located in the United States (63%). The most common clinical indications for CMR have included assessment of cardiomyopathy (21%), myocardial viability (16%), stress CMR perfusion for chest pain syndromes (16%), and evaluation of etiology of arrhythmias or planning of electrophysiological studies (15%) with assessment of cardiomyopathy representing the most rapidly growing indication in the past decade. Most CMR studies involved the use of gadolinium-based contrast media (95%). CONCLUSIONS: We present the goals, mission and vision, infrastructure, preliminary results, and challenges of the GCMR. TRIAL REGISTRATION: Identification number on ClinicalTrials.gov: NCT02806193 . Registered 17 June 2016.

ACR Appropriateness Criteria chronic chest pain-low to intermediate probability of coronary artery disease.

Chronic chest pain can arise from a variety of etiologies. However, of those potential causes, the most life-threatening include cardiac disease. Chronic cardiac chest pain may be caused either by ischemia or atherosclerotic coronary artery disease or by other cardiac-related etiologies, such as pericardial disease. To consider in patients, especially those who are at low risk for coronary artery disease, are etiologies of chronic noncardiac chest pain. Noncardiac chest pain is most commonly related to gastroesophageal reflux disease or other esophageal diseases. Alternatively, it may be related to costochondritis, arthritic or degenerative diseases, old trauma, primary or metastatic tumors, or pleural disease. Rarely, noncardiac chest pain may be referred pain from organ systems below the diaphragm, such as the gallbladder. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria(®) acute nonspecific chest pain-low probability of coronary artery disease.

This document outlines the usefulness of available diagnostic imaging for patients without known coronary artery disease and at low probability for having coronary artery disease who do not present with classic signs, symptoms, or electrocardiographic abnormalities indicating acute coronary syndrome but rather with nonspecific chest pain leading to a differential diagnosis, including pulmonary, gastrointestinal, or musculoskeletal pathologies. A number of imaging modalities are available to evaluate the broad spectrum of possible pathologies in these patients, such as chest radiography, multidetector CT, MRI, ventilation-perfusion scans, cardiac perfusion scintigraphy, transesophageal and transthoracic echocardiography, PET, spine and rib radiography, barium esophageal and upper gastrointestinal studies, and abdominal ultrasound. It is considered appropriate to start the assessment of these patients with a low-cost, low-risk diagnostic test such as a chest x-ray. Contrast-enhanced gated cardiac and ungated thoracic multidetector CT as well as transthoracic echocardiography are also usually considered as appropriate in the evaluation of these patients as a second step if necessary. A number of rest and stress single-photon emission CT myocardial perfusion imaging, ventilation-perfusion scanning, aortic and chest MR angiographic, and more specific x-ray and abdominal examinations may be appropriate as a third layer of testing, whereas MRI of the heart or coronary arteries and invasive testing such as transesophageal echocardiography or selective coronary angiography are not considered appropriate in these patients. Given the low risk of these patients, it is mandated to minimize radiation exposure as much as possible using advanced and appropriate testing protocols. The ACR Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria® acute chest pain--suspected pulmonary embolism.

Pulmonary embolism (PE) remains a common and important clinical condition that cannot be accurately diagnosed on the basis of signs, symptoms, and history alone. In the absence of high pretest probability and with a negative high-sensitivity D-dimer test, PE can be effectively excluded; in other situations, diagnostic imaging is necessary. The diagnosis of PE has been facilitated by technical advancements and multidetector computed tomography pulmonary angiography, which is the major diagnostic modality currently used. Ventilation and perfusion (V/Q) scans remain largely accurate and useful in certain settings. Lower-extremity ultrasound can substitute by demonstrating deep vein thrombosis; however, if negative, further studies to exclude PE are indicated. In all cases, correlation with the clinical status, particularly with risk factors, improves not only the accuracy of diagnostic imaging but also overall utilization. Other diagnostic tests have limited roles. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The development and review of the guidelines include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria® chronic chest pain--high probability of coronary artery disease.

Imaging is valuable in determining the presence, extent, and severity of myocardial ischemia and the severity of obstructive coronary lesions in patients with chronic chest pain in the setting of high probability of coronary artery disease. Imaging is critical for defining patients best suited for medical therapy or intervention, and findings can be used to predict long-term prognosis and the likely benefit from various therapeutic options. Chest radiography, radionuclide single photon-emission CT, radionuclide ventriculography, and conventional coronary angiography are the imaging modalities historically used in evaluating suspected chronic myocardial ischemia. Stress echocardiography, PET, cardiac MRI, and multidetector cardiac CT have all been more recently shown to be valuable in the evaluation of ischemic heart disease. Other imaging techniques may be helpful in those patients who do not present with signs classic for angina pectoris or in those patients who do not respond as expected to standard management. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Safety of magnetic resonance imaging in patients with cardiovascular devices: an American Heart Association scientific statement from the Committee on Diagnostic and Interventional Cardiac Catheterization, Council on Clinical Cardiology, and the Council on Cardiovascular Radiology and Intervention: endorsed by the American College of Cardiology Foundation, the North American Society for Cardiac Imaging, and the Society for Cardiovascular Magnetic Resonance.

Advances in magnetic resonance (MR) imaging over the past 2 decades have led to MR becoming an increasingly attractive imaging modality. With the growing number of patients treated with permanent implanted or temporary cardiovascular devices, it is becoming ever more important to clarify safety issues in regard to the performance of MR examinations in patients with these devices. Extensive, although not complete, ex vivo, animal, and clinical data are available from which to generate recommendations regarding the safe performance of MR examination in patients with cardiovascular devices, as well as to ascertain caveats and contraindications regarding MR examination for such patients. Safe MR imaging involves a careful initial patient screening, accurate determination of the permanent implanted or temporary cardiovascular device and its properties, a thoughtful analysis of the risks and benefits of performing the examination at that time, and, when indicated, appropriate physician management and supervision. This scientific statement is intended to summarize and clarify issues regarding the safety of MR imaging in patients with cardiovascular devices.